1. Field of the Invention
The present invention relates to a chassis for a sport gliding element such as a roller skate, an ice skate, and a method for manufacturing such a chassis.
2. Description of Background and Relevant Information
Such chassis must ensure the linkage between the gliding member(s) themselves, namely skate blade or wheels, rollers, and the user's foot.
The chassis is therefore generally constituted by a support surface that is capable of receiving the boot of the athlete, and by one or two lateral flanges adapted to receive the wheels, rollers or the blade of the skate.
They must also have substantial mechanical resistance characteristics while being as light as possible so as not to require too substantial forces from the athlete.
Furthermore, the increasing technicality of these sport gliding elements, especially for in-line roller skates, further increases the conflicting requirements which must be met by the skate chassis, namely:
an increased mechanical resistance and stability, especially for speed skates, but also for the so-called free ride, free style or hockey skates; PA1 some flexibility, especially in certain zones of the skate, to enable the shape of the skate to adapt to the trajectory covered, especially in curves at high speed; PA1 various and original forms to meet the emerging and changing fashion requirements; and PA1 a lowest possible manufacturing cost. PA1 costs of the molds; PA1 limited selection of materials capable of being molded; PA1 low mechanical resistance characteristics of these molding materials, even when they are metallic, and PA1 insufficient molding precision, requiring additional machining, especially with respect to alignment of the holes for fixing the wheels or the skate blade of a two-flange chassis. PA1 cutting in a metallic sheet a form corresponding substantially to the completed form of at least one portion of the chassis; and PA1 obtaining at least one stiffening rib by pressing in such portion of the chassis.
The techniques used in manufacturing the currently known chassis do not make it possible to meet all of these requirements while maintaining a reasonable manufacturing cost.
Indeed, the oldest manufacturing technique consists of making such chassis from a U-shaped bent metal sheet, as shown in the document DE 10 33 569, for example.
Such a manufacturing principle, while inexpensive, does not however make it possible to create a large variety of forms, nor a chassis with substantial mechanical resistance, unless the thickness of the metal sheet, and therefore the weight thereof, are substantially increased.
Another commonly used technique consists of making the chassis by molding from a synthetic or metallic material. Molding offers the advantage of creating various forms, but it also has numerous disadvantages:
Chassis made of composite fibers are also known. These chassis can indeed be obtained in almost all possible forms, but their manufacture is extremely expensive and difficult to industrialize. Furthermore, while such chassis are extremely rigid, they lack flexibility and are therefore fragile and "uncomfortable."
Finally, the U.S. Pat. No. 5,388,846 has proposed to make a chassis for ice skates or roller skates from a profiled, or extruded metallic bar whose transverse section corresponds to the general section desired for the chassis, the final form of the chassis being obtained after machining with removal of material.
Such a manufacturing method is also very expensive, due to the necessary machining period and to the quantity of material to be removed. It does not allow a great freedom with respect to the form or profile of the chassis.